CN103396266A - Organic matter sustained-release urea and preparation method thereof - Google Patents
Organic matter sustained-release urea and preparation method thereof Download PDFInfo
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- CN103396266A CN103396266A CN2013103464164A CN201310346416A CN103396266A CN 103396266 A CN103396266 A CN 103396266A CN 2013103464164 A CN2013103464164 A CN 2013103464164A CN 201310346416 A CN201310346416 A CN 201310346416A CN 103396266 A CN103396266 A CN 103396266A
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Abstract
The invention relates to an organic matter sustained-release urea and a preparation method thereof. A technical scheme adopted in the invention is characterized in that the total nitrogen content by weight is 40-46; the content by weight of lignin by calcium lignosulfonate is 0.3-1.5; the content by weight of methylenediurea by HCHO is below 0.6; the pH value is 5.0-7.0; and the preparation method comprises a step (1) of preparing raw materials comprising solid raw materials and liquid raw materials, and a step (2) of carrying out coating granulation. The adsorption sustained-release property of lignin realizes the good maintenance of the effectiveness of chemical fertilizers and the sustained-release of the chemical fertilizers, so the organic matter sustained-release urea is a good organic composite fertilizer material; and the exploitation researches of the lignin realizes the comprehensive utilization of natural high-molecular resources, the treatment of the environment pollution caused by the papermaking industry, the solving of the loss and pollution problems in the use process of common fertilizers, and the provision of a new product for the reduction of the agricultural production cost.
Description
Technical field
The present invention relates to a kind of slow-release carbamide and preparation method, particularly a kind of organic slow-release carbamide and preparation technology.
Background technology
The formal sizable application slow release fertilizer in domestic market is since sulfur-coated urea (SCU) in 2006 popularization.Popular on domestic market is mainly various coated carbamides: (1) thermosetting shape resene: such as epoxy, phenolic aldehyde, urea aldehyde etc.; (2) type thermoplastic resin: polyethylene, polyvinyl alcohol etc.; (3) water-soluble polymers;
The advantage of thermosetting resin or thermoplastic resin fertilizer is that time of releasing is long, but shortcoming is:
1) material is difficult in degraded in soil, generally will reach 50～60 years, uses for a long time the physical structure of meeting spoiled soil.Even if so-called degradable resin, degradable time shorten are also limited, can not accomplish degradable.
2) production unit is mostly continued to use the sweet tablet machine of pharmaceutical industry, i.e. so-called end spraying fluidized-bed can only interrupter method production, the single device small scale, and operation is trouble.
3) resin dissolves needs organic solvent, and organic solvent needs to recycle, and in removal process, has a certain amount of leakage loss, and these solvents are inflammable and explosive chemical, and safety in production needs especially in addition careful on producing.
4) raw materials cost is too high, is difficult in the application of large field.
And not yet reach a standard between water-soluble resin coated fertilizer technology.
Summary of the invention
Purpose of the present invention is exactly in view of the foregoing defects the prior art has, a kind of organic slow-release carbamide and preparation technology are provided, adopt rotary drum heavy curtain coating granulation method, to traditional technique in addition improvement and technological innovation, be that all technical process both at home and abroad are not available.
A kind of organic slow-release carbamide, technical scheme are to comprise that following composition makes, by weight:
(1) total nitrogen >=40～46;
(2) xylogen, in lignosulfonic acid calcium salt >=0.3～1.5;
(3) MDU, in HCHO≤0.6;
(4) pH value 5.0～7.0;
The preparation technology of a kind of organic slow-release carbamide that the present invention mentions comprises the following steps:
Step 1, raw material are prepared:
(1) solid material
Small particle urea and returning charge crystal seed are sent into the urea relay tank with lift, urea is from the push-pull valve discharging of storage tank bottom, fall continuously on the feed belt of electronic measuring scale, heavy curtain coating granulation rotary drum sent into and then is admitted to by urea with lift after belt scale metering;
(2) liquid starting material
Small particle urea is sent into fast ureamelting facility by lift, meanwhile part returning charge feeds above-mentioned fast ureamelting facility by worm conveyor, described fast ureamelting facility is a square structure, there is the cross scraper plate of a uniform rotation tubulation top of the superiors' horizontally-arranged, solid and the powder urea sending into or feed are struck off on tubulation, the steam that passes into relevant temperature in tubulation can be by solid or powder urea 140 ℃ of rapid meltings, time enter the reactor that bottom arranges;
Urea after melting in reactor and sulfonated lignin carry out huge legendary turtle and close with complexing action and react, then use molten urea pump to pump into the stainless steel pipes of carrying vapour insulation jacket, meanwhile, formaldehyde solution feeds this pipeline with volume pump, then by the mixing of a duct type static mixer, delivers to heavy curtain coating granulation rotary drum;
Step 2, coating granulation:
After the small particle urea particle enters heavy curtain coating granulation rotary drum, operation forward continuously by drum rotating, the plate of raising that is evenly arranged on drum inner wall is taken up urea granules come, then fall on the two-layer pallet that arranges in rotary drum and adjust, from the final material heavy curtain that forms that evenly descends on pallet.
Fusing urea meanwhile, with the lignosulfonic acid reactant salt, after by measuring instrument, being filtered, by fusing urea Pipeline transport to serial nozzle, be sprayed on the decline material heavy curtain of small particle urea formation, constantly previous operation along with single urea granules, fusing urea can be uniformly in layer coating and cladding at the outside surface of little urea granules, finally form similar onion-skin structure urea coating, the product of required particle diameter.
Further, after the coating granulation of step 2, comprise step 3, namely stoving process:
From coating rotary drum product introduction solid heat-exchanger out, carry out drying and processing, coating is processed to the moisture drying bring into the technical indicator to process stipulation; The discharging after a small amount of carbamide dust of efficient cyclone recovery is up to standard of air after drying treatment, and carbamide dust returns to Flashmelt device recycling.
Further, step 4 process for cooling
From solid heat-exchanger product out enter again another solid heat-exchanger carry out cooling, by the product cool to room temperature; The discharging after a small amount of carbamide dust of efficient cyclone recovery is up to standard of air after drying treatment, and carbamide dust returns to Flashmelt device recycling.
Further, step 5 sieving technology:
Product needed through cooling process is made sieve classification through three sieve apparatus, the oversized particles on first sieve apparatus upper strata,>5mm, be broken into particulate, then through second sieve apparatus screening, the particle on upper strata,>1mm, as the returning charge crystal seed, lower floor's screen underflow,<1mm, remove the Flashmelt device do returning charge; And the material of first sieve apparatus lower floor is through the 3rd sieve apparatus, the particle on upper strata 2～5mm as finished product, lower floor's screen underflow separately removes the second sieve apparatus; The qualification rate of screening finished product can reach 95%, and screening efficiency is in 90% left and right; Finally, finished product packing.
It should be noted that: the top of the fast ureamelting facility in step 1 is provided with induced draft fan, purpose is may produce a small amount of ammonia suction washing system during by urea melting, use recirculated water washing ammonia, after finite concentration, as ammoniacal liquor, take out, and waste gas can directly discharge.
The invention has the beneficial effects as follows: at first, the present invention adopts rotary drum heavy curtain coating granulation method, to traditional technique in addition improvement and technological innovation, be that all technical process both at home and abroad are not available; In addition, the adsorption sustained-release character of xylogen makes it can keep preferably the validity of chemical fertilizer and can make its slow release, is a kind of good compoiste fertilizer material; The development research of xylogen had both made the natural polymer child resource be fully utilized, also administered the environmental pollution that paper industry brings, solve simultaneously again loss and pollution problem in common chemical fertilizer use procedure, and can provide a kind of new product for reducing agriculture production cost.Reinforcement to the research of xylogen and application and development to promoting that resource takes full advantage of, environment protection and pulping and paper-making coodinated, continuous development has great society, economic implications.
Embodiment
A kind of organic slow-release carbamide that the present invention mentions, technical scheme are to comprise that following composition makes, by weight:
(1) total nitrogen >=40～46;
(2) xylogen, in lignosulfonic acid calcium salt >=0.3～1.5;
(3) MDU, in HCHO≤0.6;
(4) pH value 5.0～7.0;
The preparation technology of the above-mentioned organic slow-release carbamide that the present invention mentions comprises the following steps:
1, raw material is prepared
(1) solid material
Small particle urea and returning charge crystal seed are sent into the urea relay tank with lift, and urea, from the push-pull valve discharging of storage tank bottom, falls on the feed belt of electronic measuring scale continuously.Heavy curtain coating granulation rotary drum sent into and then is admitted to by urea with lift after belt scale metering.
(2) liquid starting material
Small particle urea is sent into fast ureamelting facility by lift, and meanwhile part returning charge feeds this melting device by worm conveyor.This melting device is a square form, there is the cross scraper plate of a uniform rotation tubulation top of the superiors' horizontally-arranged, solid and the powder urea sending into or feed are struck off on tubulation, the steam that passes into relevant temperature in tubulation can be by solid or powder urea 140 ℃ of rapid meltings, time enter the reactor that bottom arranges.
Fusing urea in reactor and sulfonated lignin carry out huge legendary turtle and close with complexing action and react, then use molten urea pump to pump into the stainless steel pipes of carrying vapour insulation jacket, meanwhile, formaldehyde solution feeds this pipeline with volume pump, then by the mixing of a duct type static mixer, deliver to heavy curtain coating granulation rotary drum, fast ureamelting facility and heavy curtain coating granulation rotary drum are prior-art devices, no longer describe in detail.
The top of above-mentioned fast ureamelting facility is provided with induced draft fan, and purpose is may produce a small amount of ammonia suction washing system during by urea melting, uses recirculated water washing ammonia, after finite concentration, as ammoniacal liquor, take out, and waste gas can directly discharge.
2, coating granulation
After the small particle urea particle enters heavy curtain coating granulation rotary drum, operation forward continuously by drum rotating, the plate of raising that is evenly arranged on drum inner wall is taken up urea granules come, then fall on the two-layer pallet that arranges in rotary drum and adjust, from the final material heavy curtain that forms that evenly descends on pallet.
After meanwhile fusing urea (with the lignosulfonic acid reactant salt) is filtered by measuring instrument, by fusing urea Pipeline transport to serial nozzle, be sprayed on the decline material heavy curtain of small particle urea formation, constantly previous operation along with single urea granules, the uniform in layer coating and cladding of fusing urea meeting is at the outside surface of little urea granules, final form similar onion-skin structure urea coating, the product of required particle diameter.
Due to the cooling of fusing urea curing exotherm and particle, the rotary drum domestic demand passes into a certain amount of air to take away the part heat, the discharging after a small amount of carbamide dust of efficient cyclone recovery is up to standard of this air, and carbamide dust returns to Flashmelt device recycling.
For making finished product have better slow release effect, according to the requirement of different crops and market, to the needs of the character of product, determine whether to carry out again the coating processing.The tentative mixed solution that uses polyvinyl alcohol and water glass of this technique, as the coating agent, is proceeded to process to product in the coating rotary drum.
Polyvinyl alcohol is a kind of degradable water soluble polymer, and water glass is safe from harm to soil as inorganics.In addition, also can in the coating agent, add trace element as zinc, molybdenum etc., the prior art that the mixed solution of above-mentioned polyvinyl alcohol and water glass and interpolation trace element are well known to those skilled in the art as use content such as zinc, molybdenums, no longer describe in detail.
3, oven dry
From coating rotary drum product introduction Solex solid heat-exchanger out, carry out drying and processing, coating is processed to the moisture drying bring into the technical indicator to process stipulation.The discharging after a small amount of carbamide dust of efficient cyclone recovery is up to standard of air after drying treatment, and carbamide dust returns to Flashmelt device recycling.
4, cooling
From Solex solid heat-exchanger product out enter again another Solex solid heat-exchanger carry out cooling, by the product cool to room temperature.The discharging after a small amount of carbamide dust of efficient cyclone recovery is up to standard of air after drying treatment, and carbamide dust returns to Flashmelt device recycling.
5, screening
Product needed through cooling process is made sieve classification through three sieve apparatus.The oversized particles on first sieve apparatus upper strata (>5mm) be broken into particulate, then through second sieve apparatus screening, the particle on upper strata (>1mm) as the returning charge crystal seed, the screen underflow ﹙ of lower floor<1mm ﹚ removes the Flashmelt device do returning charge.And the material of first sieve apparatus lower floor is through the 3rd sieve apparatus, and (2～5mm) as finished product, and lower floor's screen underflow separately removes the second sieve apparatus for the particle on upper strata.The qualification rate of screening finished product can reach 95%, and screening efficiency is in 90% left and right.
6, packing
Finished product packing adopts fully-automatic packaging machinery.
The advantage that the present invention brings is: China is papermaking big country in the world, and Sulfite lignin are again the main byproducts that sulfurous method is produced paper pulp or fiber pulp, derive from renewable resources.At present, except small portion is extracted utilization, over 95% xylogen, still mainly as the waste major part of industrial slurrying, by paper mill, burnt, the inorganics in Recycling of waste liquid, or simply it is entered to rivers and lakes.This has not only wasted Biological resources in large quantities, but also has caused serious environmental pollution.From environment protection and the strategy of sustainable development, xylogen is carried out to Resource analysis, have the double meaning of efficent use of resources and improvement black liquor concurrently.The exploitation Lignin in Wastewater from Paper-Making Mill is an effective way of black liquor treatment in the purposes of agriculture field.
The adsorption sustained-release character of xylogen makes it can keep preferably the validity of chemical fertilizer and can make its slow release, is a kind of good compoiste fertilizer material.The development research of xylogen had both made the natural polymer child resource be fully utilized, also administered the environmental pollution that paper industry brings, solve simultaneously again loss and pollution problem in common chemical fertilizer use procedure, and can provide a kind of new product for reducing agriculture production cost.Reinforcement to the research of xylogen and application and development to promoting that resource takes full advantage of, environment protection and pulping and paper-making coodinated, continuous development has great society, economic implications.
Claims (6)
1. organic slow-release carbamide, is characterized in that comprising that following composition makes, by weight:
(1) total nitrogen >=40～46;
(2) xylogen, in lignosulfonic acid calcium salt >=0.3～1.5;
(3) MDU, in HCHO≤0.6;
(4) pH value 5.0～7.0.
2. the preparation technology of an organic slow-release carbamide is characterized in that comprising the following steps:
Step 1, raw material are prepared:
(1) solid material
Small particle urea and returning charge crystal seed are sent into the urea relay tank with lift, urea is from the push-pull valve discharging of storage tank bottom, fall continuously on the feed belt of electronic measuring scale, heavy curtain coating granulation rotary drum sent into and then is admitted to by urea with lift after belt scale metering;
(2) liquid starting material
Small particle urea is sent into fast ureamelting facility by lift, meanwhile part returning charge feeds above-mentioned fast ureamelting facility by worm conveyor, described fast ureamelting facility is a square structure, there is the cross scraper plate of a uniform rotation tubulation top of the superiors' horizontally-arranged, solid and the powder urea sending into or feed are struck off on tubulation, the steam that passes into relevant temperature in tubulation can be by solid or powder urea 140 ℃ of rapid meltings, time enter the reactor that bottom arranges;
Urea after melting in reactor and sulfonated lignin carry out huge legendary turtle and close with complexing action and react, then use molten urea pump to pump into the stainless steel pipes of carrying vapour insulation jacket, meanwhile, formaldehyde solution feeds this pipeline with volume pump, then by the mixing of a duct type static mixer, delivers to heavy curtain coating granulation rotary drum;
Step 2, coating granulation:
After the small particle urea particle enters heavy curtain coating granulation rotary drum, operation forward continuously by drum rotating, the plate of raising that is evenly arranged on drum inner wall is taken up urea granules come, then fall on the two-layer pallet that arranges in rotary drum and adjust, from the final material heavy curtain that forms that evenly descends on pallet;
Fusing urea meanwhile, with the lignosulfonic acid reactant salt, after by measuring instrument, being filtered, by fusing urea Pipeline transport to serial nozzle, be sprayed on the decline material heavy curtain of small particle urea formation, constantly previous operation along with single urea granules, fusing urea can be uniformly in layer coating and cladding at the outside surface of little urea granules, finally form similar onion-skin structure urea coating, the product of required particle diameter.
3. the preparation technology of organic slow-release carbamide according to claim 2 is characterized in that: after the coating granulation of step 2, comprise step 3, namely stoving process:
From coating rotary drum product introduction solid heat-exchanger out, carry out drying and processing, coating is processed to the moisture drying bring into the technical indicator to process stipulation; The discharging after a small amount of carbamide dust of efficient cyclone recovery is up to standard of air after drying treatment, and carbamide dust returns to Flashmelt device recycling.
4. the preparation technology of organic slow-release carbamide according to claim 2, is characterized in that: after the step 3 stoving process, be: the step 4 process for cooling
From solid heat-exchanger product out enter again another solid heat-exchanger carry out cooling, by the product cool to room temperature; The discharging after a small amount of carbamide dust of efficient cyclone recovery is up to standard of air after drying treatment, and carbamide dust returns to Flashmelt device recycling.
5. the preparation technology of organic slow-release carbamide according to claim 2 is characterized in that: after the step 4 process for cooling, be: the step 5 sieving technology:
Product needed through cooling process is made sieve classification through three sieve apparatus, the oversized particles on first sieve apparatus upper strata,>5mm, be broken into particulate, then through second sieve apparatus screening, the particle on upper strata,>1mm, as the returning charge crystal seed, lower floor's screen underflow,<1mm, remove the Flashmelt device do returning charge; And the material of first sieve apparatus lower floor is through the 3rd sieve apparatus, the particle on upper strata 2～5mm as finished product, lower floor's screen underflow separately removes the second sieve apparatus; The qualification rate of screening finished product can reach 95%, and screening efficiency is in 90% left and right; Finally, finished product packing.
6. the preparation technology of organic slow-release carbamide according to claim 2, it is characterized in that: the top of the fast ureamelting facility in step 1 is provided with induced draft fan, purpose is may produce a small amount of ammonia suction washing system during by urea melting, use recirculated water washing ammonia, after finite concentration, as ammoniacal liquor, take out, and waste gas can directly discharge.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104817395A (en) * | 2015-04-27 | 2015-08-05 | 山东省农业科学院农业资源与环境研究所 | Controlled-release compound fertilizer and preparation method thereof |
| CN106029609A (en) * | 2014-01-09 | 2016-10-12 | 国际壳牌研究有限公司 | Urea fertiliser having improved hardness |
| CN106631630A (en) * | 2016-09-09 | 2017-05-10 | 齐鲁工业大学 | Organic slow-release nitrogen fertilizer and method for preparing same |
| CN107055652A (en) * | 2017-06-27 | 2017-08-18 | 上海泓济环保科技股份有限公司 | A kind of disc fine fack |
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| EP0188390A1 (en) * | 1985-01-18 | 1986-07-23 | Agrimont S.p.A. | Process for granulating chemical products and apparatus therefor |
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| US4676821A (en) * | 1986-12-12 | 1987-06-30 | Tennessee Valley Authority | Sulfur-coated urea |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106029609A (en) * | 2014-01-09 | 2016-10-12 | 国际壳牌研究有限公司 | Urea fertiliser having improved hardness |
| CN104817395A (en) * | 2015-04-27 | 2015-08-05 | 山东省农业科学院农业资源与环境研究所 | Controlled-release compound fertilizer and preparation method thereof |
| CN106631630A (en) * | 2016-09-09 | 2017-05-10 | 齐鲁工业大学 | Organic slow-release nitrogen fertilizer and method for preparing same |
| CN106631630B (en) * | 2016-09-09 | 2022-11-18 | 齐鲁工业大学 | Organic matter slow-release nitrogen fertilizer and preparation method thereof |
| CN107055652A (en) * | 2017-06-27 | 2017-08-18 | 上海泓济环保科技股份有限公司 | A kind of disc fine fack |
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Application publication date: 20131120 |